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1.
Management of infrastructure projects is becoming increasingly challenging due to inherent uncertainties. The most effeective way to deal with uncertainty is to collect supplementary information and knowledge. When expensive or infeasible, quantification of uncertainty may be performed using analytical or simulation techniques. The City of Edmonton, Canada has approximately 4600 km of sewer pipes in the combined, sanitary, and storm sewer local systems with uncertainty issues related to deterioration. The City has taken a proactive approach with respect to sewer rehabilitation, as it is more cost-effeective to repair a defective pipe prior to failure rather than after a collapse. This article demonstrates an approach for predicting the condition of a sewer pipe and the related cost of rehabilitation, given the limited data. Three models are described in this article that are developed to assist the City of Edmonton to effeectively plan maintenance expenditure. Each model uses a combination of rule-based simulation and probability analysis to assist in the planning of future expenditures for sewer maintenance, thereby producing an invaluable planning tool.  相似文献   
2.
High moisture extrusion using twin‐screw extruders shows great promise for producing meat analog products with vegetable proteins. The resulting products have well‐defined fiber formations and resemble real meat in both visual appearance and taste sensation. Developing reliable nondestructive techniques to quantify the textural properties of extrudates is important for quality control in the manufacturing process. In this study, we developed an image‐processing technique to automatically characterize sample fiber formation using digital imaging. The algorithm is based on statistical analysis of Hough transform. This objective method can be used as a standard method for evaluating other noninvasive methods. We have compared the fiber formation indices measured using this technique and a noninvasive fluorescence polarization method and obtained a high correlation.  相似文献   
3.
In many countries, the analogue Advanced MobilePhone System (AMPS) is progressively being replaced bydigital technologies, with the intention of maximizingcapacity and service quality. This paper considers strategies for the evolution of mobiletelephony services, employing several coexistingmultiple access technologies, such as Code DivisionMultiple Access (CDMA) and Global System for Mobile(GSM), in recovering the spectrum previously used byanalogue technologies such as AMPS. We propose partialspectral overlay and interference control strategies forCDMA systems overlaying AMPS and GSM systems, to provide smooth transition paths for introducingthe CDMA technology, and we show that these overlaystrategies lead to significant increases in overallnetwork capacity.  相似文献   
4.
This paper describes the organization and conduct of a 4th year capstone project for civil engineering students at the University of Calgary that embodied a very significant international component and the difficulties inherent to that component. The project design education process results in numerous contributions to university, industry, and society by permitting students to develop innovative design solutions that reflect multicultural influences, while also recognizing that Civil Engineering design is universal. This paper explains the novel approach adopted for the final-year civil engineering design course in 2002–2003 using the largest urban renewal project currently underway in Europe, for which the students had the opportunity to develop designs. The concept, structure, challenges, and contributions as well as the successful outcome of the civil engineering design course are also explained in the paper. Overall, this design project provided the students with valuable experience in communication, design, professional practice, and organizational skills that will be useful in their future careers, in addition to the challenges of dealing with a real and international client of a complex project.  相似文献   
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The reactive hot pressing (RHP) of Zr:C powder mixture at various molar ratios (1:0.5, 1:0.6, and 1:0.67) at applied pressures of 4‐7 MPa and 1200°C resulted in dense ZrCx ceramics. Nano‐hardness values of ZrCx are reported to be 21‐31 GPa as “x” was varied from 0.5 to 1.0. However, indentation modulus for all ZrCx compositions remained at ~350 GPa. Microhardness of the ZrCx increased from 13 to 15 GPa as the stoichiometry was increased from 0.5 to 1.0. The indentation fracture toughness for ZrC0.5 was 4 MPa m1/2, and for ZrC0.67 it was reduced to 3.6 MPa m1/2. The 3‐point flexural strength for ZrC0.5 was determined to be 386 ± 26 MPa, which decreased to 316 ± 20 MPa as the carbon content (ZrC0.67) was increased. The dry sliding wear of ZrC0.5 to ZrC0.6 indicated that the coefficient of friction was increased from 0.73 to 0.86 at 5 N load and 500 m sliding distance. Further, ZrC0.67 showed a reduction in friction coefficient of 0.81, and this was due to the increase of strong Zr–C covalent bond and unreacted graphite.  相似文献   
7.
In this study, abnormalities in medical images are analysed using three classifiers, and the results are compared. Breast cancer remains a major public health problem among women worldwide. Recently, many algorithms have evolved for the investigation of breast cancer diagnosis through medical imaging. A computer-aided microcalcification detection method is proposed to categorise the nature of breast cancer as either benign or malignant from input mammogram images. The standard mammogram image corpus, the Mammogram Image Analysis Society database is utilised, and feature extraction is performed using five different wavelet families at level 4 and level 6 decomposition. The work is accomplished through firefly algorithm (FA), extreme learning machine (ELM) and least-square-based non-linear regression (LSNLR) classifiers. The performance of the classifiers is compared by benchmark metrics, such as total error rate, specificity, sensitivity, area under the receiver operating characteristic curve, precision, F1 score and the Matthews correlation coefficient. As validation of the classifier results, a kappa analysis is included to determine the agreement among classifiers. The LSNLR classifier attains a 3% to 7% improvement in average accuracy compared with the average classification accuracy of the FA (86.75%) and ELM (90.836%) classifiers.  相似文献   
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9.
Improvements in construction engineering education result when innovative information technologies are incorporated into academic curricula. Through the use of internet-based communication technologies, no longer must students physically travel to a construction project site to observe and hear construction operations. This paper discusses two applications of internet-based, audio and video technologies currently being piloted at Iowa State University (ISU) and at the University of Calgary (UC) for the purpose of bringing live construction projects into the university classroom. Virtual Project Tours have been piloted at Iowa State University in which real-time video and audio are delivered from active construction projects to a remote classroom through the internet. The second application discussed in this paper, Virtual Supervision, is being piloted at the University of Calgary and consists of the monitoring and analysis of construction projects by using imagery gathered by web-enabled, digital cameras of fixed location transmitting video through the internet. This paper also presents a vision of a globally networked organization of engineering and construction education institutions each sharing the unique engineering and building techniques of their respective part of the globe with design and construction students located around the world. This exchange of construction project observations among the institutions will be enabled by the internet-based applications of virtual project tours and virtual supervision systems described in this paper.  相似文献   
10.
Laser speckle contrast imaging (LSCI) is a full field optical imaging technique, capable of imaging blood flow without the introduction of any exogenous dyes. Spatial and temporal resolution in LSCI images depend on how pixels are chosen from the raw image stack for contrast processing. However, all processing schemes are based on isotropic treatment of the spatial neighborhood about each pixel, restricting further improvement in spatiotemporal resolution and image quality. We present a novel spatiotemporal processing scheme for LSCI where the spatial neighborhood is anisotropic, that is, restricted along a specific direction that matches direction of blood flow. The technique allows for a significant increase in temporal resolution, from conventionally used 40 or 80 frames to just three frames; while simultaneously achieving 23% and 47% higher signal-to-noise ratios over concurrent spatiotemporal schemes, when imaging rapid and slow functional changes in blood flow, respectively. We present the concept, justification, and performance evaluation of the novel scheme and demonstrate its suitability for imaging rapid changes in blood flow. Anisotropic LSCI was able to monitor the heart rate associated fluctuations in intravascular blood flow and showed them to be as high as 28% of the mean.  相似文献   
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